Imec today reports promising
results in its Extreme Ultraviolet Lithography (EUV) mask cleaning program for
defect-free EUV masks which are crucial in achieving high chip manufacturing
yield. The research program was initiated in collaboration with mask cleaning
experts of HamaTech APE GmbH + Co. KG., a fully owned subsidiary of Süss
MicroTec AG, and some of imec’s core partners.
The objective of the dedicated EUV mask cleaning program is to develop processes
of record (POR’s) for EUV mask cleaning that not only are effective in
removing particles and organic contamination without damage to the vulnerable
materials of the EUV masks, but do not reduce mask lifetime through repetitive
cleaning. A specific EUV reticle back-side cleaning process is being developed,
to protect the electrostatic reticle chuck of the EUV scanner from degraded
performance which can negatively affect the “print on wafer” results.
Project completion is targeted for the end of 2010.
Research started after successful installation of HamaTech’s state-of-the-art
MaskTrack Pro® photomask processing system at the imec 300mm cleanroom in
early 2010, located close to the ASML EUV Alpha demo tool. A unique combination
of physical and chemical cleaning technologies have demonstrated a highly-effective
removal of organic and inorganic contamination without any negative effects
on mask integrity. The vulnerable absorber and capping layer of the reticle
presented no significant signs of deterioration.
Kurt Ronse, program director advanced lithography at imec said, “Defect-free
EUV mask availability, for achieving high chip manufacturing yield, has become
one of the major concerns for EUV lithography to become a manufacturable technology,
taking over from 193nm immersion. Besides the lack of EUV mask inspection infrastructure
and the difficulties to make defect free EUV masks, we experience day by day
how vulnerable pellicle-less EUV masks are in the wafer fab, when moved from
storage to the exposure tool and back. Until standardized EUV reticle handling
procedures can demonstrate not to add contamination to EUV mask during its normal
lifetime in the fab, the availability of an in-fab effective cleaning process
is crucial. With the results obtained so far, we are confident that it is possible
to develop effective front- and back-side cleaning processes without risks to
jeopardize the mask integrity after multiple repeated cleans.”
“We are very pleased to collaborate with imec and its leading-edge industry
partners on critical mask cleaning technology for next generation lithography
processes,” said Wilma Koolen-Hermkens, CEO of HamaTech APE. “MaskTrack
Pro is the first proven platform in the industry that can address EUVL zero
tolerance levels for particles and defects on the mask prior to exposure. With
a world-class design, the MaskTrack Pro allows clustering of metrology systems
and pod-in-pod stocking for a holistic mask management approach throughout the
life of the mask. Imec is our partner of choice to jointly develop the necessary
POR’s for our valued customers.”
Imec performs world-leading research in nanoelectronics. Imec leverages its
scientific knowledge with the innovative power of its global partnerships in
ICT, healthcare and energy. Imec delivers industry-relevant technology solutions.
In a unique high-tech environment, its international top talent is committed
to providing the building blocks for a better life in a sustainable society.
Imec is headquartered in Leuven, Belgium, and has offices in Belgium, the Netherlands,
Taiwan, US, China and Japan. Its staff of more than 1,750 people includes over
550 industrial residents and guest researchers. In 2009, imec's revenue (P&L)
was 275 million euro.
Imec is a registered trademark for the activities of IMEC International (a
legal entity set up under Belgian law as a "stichting van openbaar nut”),
imec Belgium (IMEC vzw supported by the Flemish Government), imec the Netherlands
(Stichting IMEC Nederland, part of Holst Centre which is supported by the Dutch
Government), imec Taiwan (IMEC Taiwan Co.) and imec China (IMEC Microelectronics
(Shangai) Co. Ltd.).